Write JSON

#include <iostream>
#include <nlohmann/json.hpp>
#include <iomanip>
#include <vector>
#include <fstream>

using json = nlohmann::json;
int readJSON(){
  json i_data;
  std::vector<std::string> ids = i_data["id"];
  std::vector<int> counts = i_data["count"];
  json o_data;
  o_data["id"] = ids;
  o_data["count"] = counts;
  std::ofstream os("o_data.json");
  os << std::setw(4) << o_data << std::endl;
  std::cout << "write complete" << std::endl;
  return 0;
}